Apple has marked the tenth anniversary of the iPhone by launching a brand new flagship model - the iPhone X.

The company will be hoping that the new device, coupled with a new iPhone 8 and 8 Plus, will reinvigorate sales of its smartphones which have flagged in the last year.

The new handset features a new 5.8 inch Super Retina display with HDR which covers almost the entire front of the phone.

That means the home button and fingerprint sensor on the device have disappeared, replaced instead by a new facial recognition system for unlocking the phone.

FaceID projects 30,000 infrared dots onto the user's face and uses a new neural engine, depth sensing technology and machine learning to determine if they are authorised to unlock.

Apple says there is a one in a million chance of a person being able to unlock someone else's iPhone X using FaceID.

Because the home button is gone, a swipe up from the bottom of the screen takes the user to the home screen.

The iPhone X can be woken by a tap or by picking it up. Siri is activated using voice or by holding the power button.

It also has a new Animoji feature which enables emojis to be animated with the user's voice and expressions.

Apple says the new device is also tuned for Augmented Reality applications with new hardware and software that enable AR technology to work.

The device also has new dual 12MP camera sensors, dual optical image stabilisation and a new portrait mode that allows the lighting of the subject to be artificially manipulated.

The front side True Depth camera also has a new portrait mode.

For the first time Apple has added wireless charging to the new handset, adopting the Qi wireless charging standard.

It has also developed a new mat, called AirPower, for iPhone, Watch and Airpod wireless charging, although it won't be available until next year.

The iPhone X will be available with 64GB and 256GB and will cost from $999. Orders can be placed from October 27th with the device shipping from November 3rd.

Apple also unveiled a new iPhone 8 and 8 Plus featuring new displays, new cameras and wireless charging.

The new handsets have glass front and back and new Retina screens.

The iPhone 8 Plus has a dual camera with a new 12MP sensor.

However, while the iPhone 8 camera has also been upgraded, it remains a single camera unit.

The cameras can record in 4K and there is a new slo-mo mode which allows 1080p video recording at 240fps.

The handsets are available in silver, space grey and a new gold finish and also have new stereo speakers.

Apple says the iPhone 8 models have also been optimised for Augmented Reality applications.

Apple has also launched a new version of its watch - the Watch Series 3.

As expected, it has cellular connectivity built in, which means users can access maps, music and other internet dependent services while on the move, without having to tether to an iPhone.

Series 3 Watch also has a dual core processor and the Siri assistant can now speak through it.

Although it has new technology inside, the new Watch has the same size case as the previous version.

The cellular version will not be available in Ireland at launch, but the Series 3 model without the mobile connectivity will.

It will cost $329, with the cellular version priced at $399. Orders will open on 15 September, with first shipments beginning on 22 September.

The new timepiece will run on the new Watch OS4, which will be available from 19 September.

Among its new features is an enhanced heart rate monitor app, which will alert the user when their heart rate is abnormal.

As rumoured, Apple also unveiled a new 4K HDR Apple TV which Tim Cook described as "a new inflection point".

The company said it has been working with Hollywood studios and TV production companies to bring more 4K content to the iTunes store.

It is also adding Live Sports to the Apple TV app.

The announcements were made at a press event at the new Steve Jobs Theatrr on Apple's new multibillion dollar campus in California.

At the start of the event, CEO Tim Cook paid an emotional tribute to the co-founder of the company.